Road-breaking apparatus



J. .J. MAGEE 1mm) BREAKING APPAIiATUS May 5, 1931.

Filed Jan. 27, 19:50 3Sheets-Sheet 1 y ,1931. J. J. MAGEE 1,804,360

. V ROAD BREAKING APPARATUS Filed Jan. 27,1930 3 Sheets-Sheet 2 May 1931' .J. J. MAGEE v 1,304 ROAD BREAKING APPARATUS 3Sh86ts eet 3 Filed an. 27, 19:50

noll I I a W43 0 Patented May 5, 1931 PATENT OFFICE JOHN J. MAGIEE, F WOODBUR Y, JERSEY ROAD-BREAKING APPARATUS Application filed January 27, 1930. Serial No. 423,874.

This invention relates to road-breaking apparatus andmoreparticularly to an appara tus for breaking concrete roads. 7

An importantobject of the invention is the provision of apparatus permitting use of an ordinary fluid pressure hammer, such as employed in pile driving,.in this connection and permitting the suspension of the hammer from the boom of an ordinary steam shovel from which the scoop has been removed.

Ordinarily use of apparatus of this character is impossible due to the fact that a chisel driven by such a hammer may suddenly break through the concrete strata which yaries thickness in different roads, and often in the same road, from three to eighteen inches, thereby allowing the poundingof the hammer to be brought to bear against solid portions ofthe apparatus which would tend to tear the hammer from its fastening and to otherwise destroy the same.

Accordingly, an important and more specific object of the invention is the provision of means positively limiting movement of the chisel when theroad bed has been perforated and for cushioning blowsofthe hammer occurring after perforation of the road bed and before the hammer can be shut down and 3D shifted to a new position.

ings wherein, for the purpose of illustration, '1 have shown a preferred embodiment of my invention and wherein? r j Fig. 1 is a sideelevatio-n of road'breaki'ng apparatus, constructed in accordance with my invention; v V i Fig. 2 's a vertical sectional View through thehammer andthe associated chisel-mechan I c. Fig. 3 is a side elevation thereof; Fig. 4 is a combined perspective of the ele ments of the cushioning apparatus; Fig.5 is a perspectiveiof one form of chisel; p

I Fig. 6' is a sectionalview showing the secon-djform'of chisel, mounted in the hammer mechanism; i i Fig; 7 is a sectional view on line 7-7 of so 1 These and other objects I attain by the con- 7 struction shown in the accompanying draw- Fig. is a vi'ew'similar to Fig. 6 showing thechisel of. Fig. 5 in use and the parts the position which they occupy after the chisel has broken through the concrete. FFig. 9 is a sectional view on line 9 9 of 1 U Fig. 10 is a perspective View of the chisel guide; and 1 Fig. 11 is a perspective view of the brake element. I

Referring now more particularly to the drawings, the numeral 10 generally designates the boom of an ordinary steam shovel which, as is well known to those familiar with the art, is swingable and adjustable in its mountings upon the shovel platform 11 and may, accordingly, be shifted to cover con siderable area. In accordance with my invention I support from this boom an ordinary steam hammer structure generally designatedat 12 including the usual ham mer element 13 reciprocated by piston 14 and by its reciprocation controlling valving of the operating fluid to the hammercyl'inde'r through means generally designated at 15. The hammer element co-acts with an anvil 16 mounted in suitable guides '17 carried by the hammer structure 12. To these guides I secure a cushion element'lS which, as more clearly shown in Fig. 4,'is composed of metallic side plates 19 securing together and to the guides 17 blocks 20 of wood or any other suitable resilient material. The blocks in assembled relation define an opening '21 in which is 'slidably mounted a chisel. This" chisel may be of such cross section, at the point of its passage through the opening" 21 in which it fits, that rotation of the chisel is prevented as suggested by the construc tion illustrated at 22 in Fig. 5, or may be of such conformation that the chisel may rotate therein as suggested in the construction of Figs. 6 and 7 o The guides, through the securing elements of the plates, further support a guide element 23 for the chisel, this, guide element. being preferably in the form of a metal yoke through which the chisel is slidable and having an aperture conforming to'the shaping of the chisel as in the case of the cushioning block structure just described. The chisel 22 at its upper end is provided with an outstanding flange 24 adapted to limit downward movement of the chisel with relation to the guides and adapted to engage in a seat 25 formed in the cushioning block structure 18 for its reception when the chisel is in its lowermost position and is unsupported from the ground. The upper end of the chisel has a head 26 to engage in a recess 27 formed in the under surface of anvil 16.

Secured upon the chisel 22 below the cushioning guide is a further combination cushioning element and brake generally designated at 28. This element is at present shown in the form of a pair of wood block sections 29 clamped upon the chisel and hav ing a very firm frictional engagement therewith.

In use of the apparatus the chisel is rested upon the concrete surface which is to be broken up and the weight of the hammer mechanism imposed thereon. This weight will cause the guides and brake element 28 to slide downwardly upon the chisel. until the parts occupy the position shown in Fig. 2. The hammer is then started and by its repeated blows throws the chisel downwardly into the concrete the parts remaining in the position illustrated until the chiselfinally perforates the concrete when it will move downwardly suddenly together with the supported weight of the hammer mechanism, The sudden downward movement will cause the separation of the brake element 28 and the cushioning mechanism and the brake element coming into engagement with the concrete" will cause a momentary check of the chisel until the succeeding hammer blow drives the chisel downwardly through the brake bringing the cushioning element into engagement with the upper surface of the brake. At this time the anvil 16 will be resting upon the upper surface of the cushion which is solidly supported through the brake from the concrete and any blows applied by the hammer element before the flow of operating fluid to the hammer structure is cut off will be cushioned through the cushioning ele ment and .brake and will not cause any damage to the hammer structure such as ordinarily results when the parts are suddenly freed. While brake element 28 can be elimi-' nated and the depth of cushion structure 18 slightly increased the structure illustrated is preferred in that the brake element provides for a more gradual check of the force of the first blow after resistance to the chisel ceases, which blow is most likely to cause damage to the parts. Succeeding blows after the parts reach the position shown in Fig. 8 will result in a bouncing of the hammer in the guides from the reaction of the cushioning element so that the anvil gives forth a ringing sound indicating completion of the operation.

It will be obvious that apparatus of this character may be readily incorporated in any hammer structure without material change in the ordinary structure thereof and will provide insurance against loss otherwise incurred through breakage of the hammer.

It will also be obvious that the structure employed is capable of a certain range of change and modification without departing from the spirit of my invention, I accordingly do not wish to be understood as limiting myself thereto except as hereinafter claimed.

I claim:

1. In road-breaking apparatus, a support, an air hammer structure depending from the support and including the usual reciprocable hammer element and anvil with which the hammer element co-acts and guides within which the anvil element is vertically movable,.a cushioning structure supported from said guides and a chisel slidable in the cushioning structure, said cushioning structure and chisel having co-acting means limiting downward movement of the chisel, the chisel when in its lowermost position permitting the anvil to seat upon said cushioning structure.

2. In road-breaking apparatus, a roadbreaking chisel, a cushion guide for the chisel having means limiting downward movement of the chisel and means supporting the guide and mounting an element for applying successive blows to the head of the chisel, said element engaging the guide and being supported thereby when the chisel is in its lowermost position.

3. In road-breaking apparatus, a support, an air hammer structure depending from the support and including the usual reciprocable hammer element and anvil with which the hammer element ,co-acts and guides within which the anvil element is vertically movable, a cushioning structure supported from said guides, a chisel slidable in the cushioning structure, said cushioning structure and chisel having co-acting means limiting downward movement of the chisel, the chisel when in its lowermost position permitting the anvil to seat upon said cushioning structure and friction brake carried by the chisel and adapted to engage the road upon passage of the chisel therethrough. I

4. In road-breaking apparatus, a roadbreaking chisel, a Vertically movable guide for the chisel having means limiting downward movement of the chisel and a hammer element for imparting successive blows to the head of the chisel through an interposed anvil, said guide being of cushioning material and receiving and supporting the anvil when the chisel is in its lowermost position.

5. In road-breaking apparatus, a roadbreaking chisel, a vertically movable guide for the chisel having means limiting downward movement of the chisel, a hammer sale ment for imparting successive blows to the head of the chisel through an interposed anvil, said guide being of cushioning material and receiving and supporting the anvil when the chisel is inits lowermost position, and a friction yoke slidable upon the chisel beneath the guide.

6. In road-breaking apparatus, a roadbreaking chisel, means for imparting successive blows to the head of the chisel to force the same through the road bed, a friction brake upon the chisel and adapted to engage the road bed when the chisel passes therethrough to fri'ctionally resist further downward movement of the chisel.

7 In road-breaking apparatus, a roadbreaking chisel, means for imparting successive blows to the head of the chisel to force the same through the road bed, a friction brake upon the chisel and adapted to engage the road bed when the chisel passes therethrough to frictionally resist further downward movement of the chisel and a guide for said chisel seating upon said friction brake after a predetermined downward movement of the chisel. I

8. In road-breaking apparatus, a roadbreaking chisel, means for imparting successive blows to the head of the chisel to force the same through the road bed, a friction brake upon the chisel and adapted to engage the road bed when the chisel passes therethrough to frictionally resist further downward movement of the chisel and a guide for said chisel seating upon said friction brake after a' predetermined downward movement of the chisel. said guide being of cushioning material and receiving the impact of the first-named means when the chisel is in said position.

9. In road-breaking apparatus, a roadbreaking chisel, means limiting downward movement of the chisel, a hammer element for imparting blows to the head of the chisel through an interposed anvil, the chisel limiting means comprising a cushioning element receiving and supporting the anvil when the chisel is in its lowermost position.

10. In road-breaking apparatus, a chisel, a hammer operating upon the chisel through an interposed anvil, a friction brake for the chisel limiting downward movement of the chisel and providing a seat for the anvil when the chisel is in its lowermost position.

JOHN J. MAGEE, 

